Rainbow Road to St Arnaud

Rainbow Road cuts 63 kilometers through the heart of Nelson Lakes National Park, following old gold mining routes from the 1860s that carved their way up the Wairau Valley. The track starts innocently enough from Highway 7 but soon turns serious with multiple unbridged creek crossings, including the notorious Ada River ford that’s claimed more than a few bumpers. At Hanmer Pass (1145m), you’ll cross the Main Divide with views stretching across both Canterbury Plains and Tasman Bay on clear days.

This is expert-level terrain demanding articulated 4WD with diff-locks and underbody protection. The Ada River crossing alone can be impassable after heavy rain, trapping vehicles for days. Best tackled December through March when snow’s cleared but creek levels remain manageable. Carry recovery gear, extra fuel, and supplies for 2-3 days — the nearest help is hours away. The reward is access to some of South Island’s most pristine high country, plus the satisfaction of completing one of New Zealand’s most challenging legal 4WD routes.